Minimal Erythema Dose Determination in Holstein Friesian Cattle

Cattle on pasture are continuously exposed to solar UV radiation, which has been associated with biological effects such as sunburn, photosensitization, squamous cell carcinoma, and cutaneous vitamin D3 production. The minimal erythema dose (MED) required to produce first-degree sunburn (erythema) is poorly researched in cattle. Since cattle are naturally covered with dense hair coats, the MED is influenced by the UV protection offered by the hair. The objective of this study was to determine the MED on intact-hair-covered (MED-H) and shaved white skin (MED-S) of Holstein Friesian cattle. Twenty-one Holstein Friesian cows and heifers were MED tested using a narrowband UV-B LED light (peak irradiance at 292 nm) on eight hair-covered and eight shaved areas over white skin previously unexposed to direct sunlight. Erythema was visually assessed after 24 h. The mean MED-H and MED-S were 5,595 and 329 J/m2, respectively. Heifers had a higher MED-H compared to cows, 7,600 and 4,969 J/m2, respectively. The mean UV transmittance of white cattle hair was 6.7%. MED-H was correlated with hair length (Spearman's rho = 0.76). A linear regression model showed that each millimeter of hair coat length increased the MED-H by 316 J/m2. In conclusion, this study provides a MED testing protocol for cattle and reports standardized values of MED for cattle on intact-hair-covered and shaved areas.

Trichobezoars in the practice of a pediatric surgeon

Material and methods. A retrospective analysis of medical records of two children. Anamnestic, clinical, diagnostic and intraoperative findings were analyzed.Purpose. To describe cases of trichobezoars in children : occurrence, diagnostics and treatment.Results. In the first case, a girl, aged 5, often swallowed her own hair after a psychological trauma; and at the age of 15 she complained of hair loss and anemia. In the second case, a boy was chewing and swallowing his own hair for 6 months under the emotional stress. Two weeks before hospitalization he complained of abdominal pain. In both cases, there were no history of intestinal obstruction. At the fibroesophagogastroduodenoscopy, foreign bodies were visualized which were diagnosed as trichobezoars. X-ray diagnostics confirmed foreign bodies in both patients. Those bodies had the shape of the stomach and had an inhomogeneous porous structure. The patients were operated: laparotomy, gastrotomy with removal of dense hair formation. Postoperative course was uneventful.Conclusion. Psychological situations provoked in children the obsessive trichotillomania and trichophagia due to which large trichobezoars were formed in the stomach.

Quality of hair-coat covering and skin of Karakul lambs bred in Kalmykia

Karakul breed of sheep is one of the oldest breeds. For the development of semi-desert pastures more than 176 thousand heads of Karakul sheep of gray and black colors were brought to the Republic of Kalmykia from the republics of Central Asia and Kazakhstan. Scientists of the Kalmyk Scientifi c and Research Institute of Agriculture and practical breeders were tasked with creating specialized herds of Karakul sheep of diff erent colors and krimmer lamb types that produce high-grade krimmer lambs. The purpose of the research was to study the quality of hair-coat covering and skin of Karakul lambs bred in Kalmykia. Some qualities of the hair-coat covering and skin of gray and black Karakul lambs in the APC “Polynny” and “Erdnievsky” have been analyzed in the article. The physical and mechanical parameters of the hair-coat covering and skin of Karakul lambs have been studied: the length of the hair in the curl, the hair tone, the degree of silkiness and shine, and the total thickness of the skin. Karakul lambs of black and gray color have diff erent properties of hair-coat covering; lambs of gray color have longer and thinner hair, relatively less shiny, dense hair-coat covering. The average length of white hairs in the rump area of the gray karakul was by 2,4±0,2 mm or 22 %, black hairs by 0,3±0,2 mm or 2,7 %, in the withers by 2,0±0,3 mm and 0,2±0,3 mm longer, respectively, than in similar areas of the black karakul skins. In the lambs of gray color more thick and rather loose skin than in lambs black color. Thus, the skin thickness of gray lambs was by 176 microns or 6,7 % more than black lambs. The primary follicles of white hairs are by 559 microns deeper, and the secondary follicles are 200 microns deeper than the hair follicles of black lambs. Features of the hair cover of lambs of diff erent colors are shown in absolutely identical conditions of feeding and housing, these diff erences should be taken into account when improving of Karakul sheep.

A new mayfly species of Rhoenanthus (Ephemeroptera: Potamanthidae) from Peninsular India

A new mayfly species, Rhoenanthus (Rhoenanthus) tungaiensis sp. nov. is described and characterized at the larval stage by fore tibiae relatively long with dense hair like setae on dorsal and lateral surface, male compound eyes large, mandibular tusks 0.8 times longer than head length, segment I of maxillary palpi 1.7 times longer than segment II, fore femur 2.9 times longer than its greatest width, gill III with 46–48 marginal fibrillae on lateral margin of dorsal lamellae and 35–37 on ventral lamellae. At the imaginal stage, the new species can be separated by inverted bell shaped markings on terga, purplish brown intercalaries in forewings, costal cross veins reddish brown and infuscated, MP2 connected to CuA basally.

Optical Properties of Hairs During the Early Stages of Leaf Development in Platanus orientalis

Young, developing leaves of plane (Platanus orientalis L.) possess a dense hair cover on both surfaces but, as the leaf matures, the hairs of the upper surface abscise, leading to a glabrous epidermis. Leaf hairs strongly attenuate visible radiation, partly due to high reflectance of the trichome layer and partly to the presence of an absorbing pigment, tentatively identified as the anthocyanidin peonidin, which was present in the hairs of exposed young leaves but was absent on leaves harvested from the interior of the canopy. It is suggested that leaf hairs, apart from other functions, may protect developing leaves against the photoinhibitory effect of excess light.